Question

$2\text{g}$ of butane is burnt with an excess of oxygen to form $C{O}_2$. What is the approximate amount of $C{O}_2$ formed?

• A. $2\text{g}$
• B. $3\text{g}$
• C. $1.5\text{g}$
• D. $6\text{g}$

Answer 1

The correct option is D $6\text{g}$

The balanced equation is :
$C_4{H}_{10}+\frac{13}{2}{O}_2\to 4C{O}_2+5H_{2}O$
$\text{Number of moles of butane}=\frac{\text{Given mass}}{\text{Molar mass}}=\frac{2\text{g}}{58\text{g/mol}}=0.0345\text{mol}$
1 mol of butane produces 4 mol of $C{O}_2$.
0.0345 mol of butane will produce $(4\times 00345)=0.138\text{mol}C{O}_2$
Amount of $C{O}_2$ produced $=\text{No. of moles}\times \text{molar mass}$
$=0.138\text{mol}\times 44\text{g/mol}$
$=6.07\text{g}$